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Chapter 6: Q. 3.2 (page 393)

Refer to the previous Check Your Understanding (page 390 ) about Mrs. Desai's special multiple-choice quiz on binomial distributions. We defined X=the number of Patti's correct guesses.

1. Find μX. Interpret this value in context.

2. Find localid="1649452775386" σX. Interpret this value in context.

Short Answer

Expert verified

The standard deviation value ofσXis1.265

Step by step solution

01

Given Information 

Number of questions=10

Students are supposed to guess the answers.

Xis a number of answers that Patti gives correct.

Probability of success(p)=0.2

02

Explanation

Compute the mean using binomial distribution is:

σX=n×p×(1-p)

Calculation:

The standard deviation of Xis computed as:

localid="1649854842527" σX=n×p×(1-p)=10(0.2)(1−0.2)=1.265.

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